CN103140441B - The expanded graphite agglomerate pulverized, its preparation method and application thereof - Google Patents

Abstract

The disclosure relates to the expanded graphite agglomerate composition of pulverizing, the method for the manufacture of this kind of agglomerate, and they are as the purposes of conductivity additive, and comprises the conductive composite material of expanded graphite agglomerate of this kind of pulverizing.The disclosure also relates to is preparing the purposes in thermally conductive materials for the manufacture of the method for this kind of matrix material and this kind of matrix material.The feature of these agglomerate is, such as by a certain softness that the shearing force during mixing applied allows agglomerate to dissolve, to cause the feed performance of the improvement of expanded graphite meterial in composite matrix and the distribution of high uniformity thus.

Description

The expanded graphite agglomerate pulverized, its preparation method and application thereof

Related application

This application claims the rights and interests of U.S. Provisional Application 61/372, the 479 and EP application number 10172468.0 submitted on August 11st, 2010, its full content is herein incorporated for reference.

Technical field

The disclosure relates to the purposes of the expanded graphite agglomerate composition of the pulverizing as conductive additive, its preparation method and their (such as polymeric blends, pottery and inorganic materials) in the composite thereof.

Background technology

Graphite Powder 99 is the promising weighting agent (that is, conductive additive) for heat conduction and conductive polymers and other matrix materials.

The graphite (expandedorexfoliatedgraphite) (also referred to as nano-graphite or nanostructure graphite) expanding or peel off, because the heat conduction of its excellence and conduction property attract increasing concern recently.Be transported in the thermal conductivity on polymkeric substance or other materials (such as cement or gypsum material), expanded graphite is better than unexpansive graphite and other conductive fillers (such as, boron nitride, carbon fiber, carbon nanotube).It is generally known in this area for expanded graphite being added in flooring material to the thermal conductivity being used for improving matrix material, and is such as described in DE-OS-10049230A1.

But, contrary with natural graphite with the synthesis of conventional height crystallization, be the difficulty of its workability and workability by the shortcoming that expanded graphite adds in polymer material, its lubricity is lower, its oxidation-resistance is lower and dustiness.In addition, process expanded graphite and can produce flow problem in polymer mixer, this makes to be difficult to extrude the polymkeric substance comprising expanded graphite.Go wrong during expanded graphite being fed in forcing machine especially.

The US2009/0189125 licensing to the people such as Grigorian describes the method for the preparation of conducting polymer composite material, comprise and not pre-dispersed carbon is mixed with the emulsion comprising the polymkeric substance be in liquid solvent, thus obtain the dispersion liquid of the carbon be in polymeric matrix, from dispersion liquid, and then remove solvent (" solution mixing (solutioncompounding) ").The people such as Grigorian are the laboratory scale process with the formal description of comparing embodiment also, wherein by mechanically mixing (mixing) (mixture (compounding)), and then mixture is molded as composite sheet and expanded graphite is mixed with dry polypropylene powder.The people such as Grigorian do not describe any workability problem observed for expanded graphite, such as to by expanded graphite are fed to problem relevant in forcing machine.

In addition, the conductive additive of the gypsum material that the expanded graphite particles of the compacting that the US2007/031704 licensing to SGLCarbon describes for being manufactured by the graphite flake by pulverizing forms.First, expanded graphite is compressed into there is thickness and 0.8 to 1.8g/cm between 0.1 to 3 millimeter ³between the larger two-dimensional structure (i.e. graphite flake) of density, be then chopped in cutting machine and there is 1 to 5 mm dia and typically at 0.12 to 0.25g/cm ³between the comparatively small-particle of volume density.The particle obtained compared with the present invention is different in their characteristic, and particularly in pellet hardness, in the particle described in US2007/031704, it is higher significantly.Especially, with powder expansion graphite-phase ratio, the hardness of the expanded graphite particles described in US2007/031704 has negative interaction to the thermal conductivity of combination product and to its mechanical property.

EP0735123A describes the method for the manufacture of the graphite composite material based on expanded graphite and for chemical heat pump or industrial gasses treatment unit.In the method described in EP0735123A, by compression or lamination, pre-for expanded graphite densification is changed into large size matrix or thin plate.Then by injecting and drying subsequently, and then final compression step is further processed this composite compact, thus makes graphite products become its final form of wishing.EP0735123A does not describe the purposes of graphite as conductive additive, such as, for polymeric articles.

The US2008/0279710A1 of the people such as Zhamu describes the method that manufacture is used as the conducing composite material composition of fuel cell double polar plate especially.The method comprise make expandable (with expand relative) Graphite Powder 99 mixes with nondistensible Graphite Powder 99 and tackiness agent, then passes through the graphite of thermal treatment inflating inflatable.Subsequently, mixture is compressed into the composite compact that large size is shaping in advance, such as thin slice and block, then it processed thus activate the tackiness agent in composition, obtain the composition board (such as, see, the schema in Fig. 2 a) of the hope that can be used in fuel cell.Present patent application seems to describe to expand and comprises the expansible black lead part of the mixture of expansible black lead, non-expansible black lead and tackiness agent, and carry out curing mixture by combination compression and adhesive treatment subsequently, thus generation has good mechanical integrity, shows the matrix material of higher transverse conduction simultaneously.The people such as Zhamu do not consider the powdered graphite expanded, but prepare mixture with tackiness agent, thus directly generate the composite compact of the hope caused due to their process.Be difficult to process (when can consider that such as non-expansible black lead mixes with other powder) although US2008/0279710A1 proposes expanded graphite, the solution provided for this problem is more suitable for the forward slip value two kinds of Graphite Powder 99s peeled off at expansible black lead, evades the reluctant problem that the low density due to expanded graphite causes thus.

Therefore, the object of this invention is to provide expanded graphite form, it keeps thermal conductivity and the electric conductivity of the excellence of Powdered expanded graphite, provides the comparable good workability that must go up standard substance (namely unexpansive synthesis or natural graphite) simultaneously.Other object is to provide the method for the preparation of this kind of favourable expanded graphite form, and provides the matrix material comprising this kind of favourable expanded graphite form in addition.Finally, another object is to provide application and the purposes of the conductive polymers comprising described favourable expanded graphite form again.

Summary of the invention

The present inventor finds that expanded graphite can be pulverized and be processed into the expanded graphite agglomerate of pulverizing subsequently, described expanded graphite agglomerate is softer, namely substrate material (such as polymkeric substance) period is joined or these agglomerate " dissolving " are (namely afterwards at them, separate coalescent) become relatively fine particle, generate the conducing composite material with excellent thermal conductivity (and electric conductivity) thus, keep the mechanical stability of matrix material simultaneously.In addition, compared with unprocessed expanded graphite, agglomerate provides better treatability, inter alia, this provides graphite additive more easily add in polymkeric substance at conductive polymers production period.

Therefore, according to first aspect, the present invention is directed to the graphite agglomerate of the expanded graphite particles comprising pulverizing compacted together.This kind of agglomerate represents the relative powder (even if having larger particle diameter) that still can flow of expanded graphite particles with the compacting of thin slice or other three-dimensional composite compact forms.

In other words, graphite agglomerate of the present invention represents particulate matter, it is characterized in that such as according to its size distribution that DIN51938 is determined by soft vibrosieve.Such as, some embodiment of the expanded graphite agglomerate of pulverizing of the present invention is preferably characterised in that size distribution, wherein be retained in the sieve of 250 μm according in the analysis of DIN51938 from about 10wt% to about 80wt%, or be retained in 500 μm of sieves from about 10wt% to about 60wt%, or be retained in 1 mm sieve to about 30wt% from about 10wt%, or be less than about 5wt% and be retained in 2 mm sieve.In addition, some embodiment of the expanded graphite agglomerate of pulverizing of the present invention be preferably characterised in that have scope from about 100 μm to about 10mm or from about 200 μm of particles to about 4mm size.

In addition, this kind of agglomerate can have pellet hardness/softness, between the processing period for the preparation of conductive polymers, this allows particle at least in part and preferably substantially separates coalescent completely, namely solution gathers into and has well lower than 250 μm or even lower than the particle of the median size of 100 μm, this causes " dissolving ", and expanded graphite particles is uniformly distributed in the polymer matrix.In some embodiments, the component that at least one that graphite agglomerate of the present invention can comprise particulate form is other, such as natural graphite, synthetic graphite, carbon black, boron nitride, aluminium nitride, carbon fiber, carbon nanofiber, carbon nanotube, Graphene, coke, silver powder, copper powder or their combination.Naturally, agglomerate described herein does not comprise the extra component worked as tackiness agent, described tackiness agent by slacken generation agglomerate desired by particle softness.

According to second aspect, the present invention is directed to the method for the expanded graphite agglomerate for the manufacture of pulverizing of the present invention, wherein said method comprises expanded graphite agglomerate that is compacted together for the expanded graphite particles of pulverizing thus formation pulverizing.In some embodiments, the method comprises pulverizing expanded graphite meterial further, thus preparation needs the parent material of the restriction used during the compacting step for the preparation of agglomerate.Alternatively, the method can also comprise prepares expanded graphite by natural or synthetic graphite material, and this can by inserting graphite material and graphite material thermal expansion being realized subsequently thus form expanded graphite meterial.For the preparation of the general process flow diagram flow chart of some embodiment of the expanded graphite agglomerate of pulverizing of the present invention shown in Fig. 1.

Therefore, the expanded graphite agglomerate by the pulverizing of aforesaid method acquisition is other aspect of the present invention.

Another aspect again of the present invention is for providing conductive polymers, described conductive polymers comprises the expanded graphite agglomerate of pulverizing of the present invention, or comprise by by expanded graphite meterial compacting or be molded as large-size particle (such as, exfoliated graphite sheet as known in the art) and the expanded graphite particles of the compacting of preparation, then grind molded expanded graphite particles, shred or be milled into the particle of the expanded graphite of the compacting of tool size likely and size distribution.Suitable polymkeric substance comprises, but be not limited to, polypropylene (PP), high density polyethylene(HDPE) (HDPE), Low Density Polyethylene (LDPE), linear low density polyethylene (LLDPE), polymeric amide, polyester, poly-arylene sulfide (polyarylenesulfide), polyarylene oxides (polyaryleneoxide), polysulfones, polyarylester, polyimide, poly-(ether ketone), polyetherimide, polycarbonate, elastomerics (such as, synthesis and natural rubber), thermoplastic elastomer, their multipolymer or their mixture.

Finally, other aspect of the present invention considers the purposes of this kind of conductive polymers in preparation heat conduction and electro-conductive material, these heat conduction and electro-conductive material can be used in multiple application, such as, heat dissipation in LED illumination, solar panel, electronic installation etc., or the heat exchanger material such as in underground heat flexible pipe, floor heating and other related application.

Accompanying drawing explanation

For the preparation of the general schema of the method for the particular implementation of the expanded graphite agglomerate of pulverizing of the present invention shown in Fig. 1.

Fig. 2 a illustrates that the feed performance of the expanded graphite agglomerate pulverized at the maximum output facet from BrabenderFlexWallDDW-MD5-FW40Plus-50 gravity dosemeter and simple helix forwarder increases, and it be the function of the tap density of the embodiment of expanded graphite agglomerate for pulverizing.The maximum output of the same apparatus from the expanded graphite agglomerate being used for pulverizing compared with other materials known in the art, is comprised exfoliated graphite sheet, standard synthetic graphite and the carbon black of milling by Fig. 2 b.Fig. 2 c illustrates the cross section of fracture flexural strength sample.Left hand view: the KeyenceVK-9700 laser scanning image with the PPH-graphite compound (namely according to the embodiment of the expanded graphite agglomerate of pulverizing of the present invention) of 25%GEGA; Right part of flg: the SEM picture with the PPH-graphite compound (that is, the expanded graphite powder (not coalescent) of the pulverizing of TIMCALGraphite & Carbon) of 20%UP.

Fig. 3 a illustrates longitudinal thermal conductivity of homopolymer polypropylene (PPH, the SabicPP576P) sample of the embodiment of the expanded graphite agglomerate comprising pulverizing and horizontal thermal conductivity, is the function of carbon content.The sample that Fig. 3 b compares the expanded graphite agglomerate of the pulverizing containing 20wt% again and the exfoliated graphite sheet of milling containing 20wt%, standard synthetic graphite, carbon black and longitudinal thermal conductivity of completely additive-free (100%PP) sample and horizontal thermal conductivity.

Fig. 4 compares the homopolymer polypropylene (PPH of the expanded graphite agglomerate of the pulverizing containing 20wt%, SabicPP576P) sample of sample and the exfoliated graphite sheet of milling containing 20wt%, standard synthetic graphite and carbon black, by the volume specific resistance determined according to the four point cantact methods of DIN51911.

Fig. 5 describes conductive polypropylene homopolymer by the thermal conductivity determined according to the four point cantact methods of DIN51911 and volume specific resistance, is the function of the content (by weight) of the expanded graphite agglomerate of the pulverizing of some embodiment according to the present invention.

Fig. 6 a and 6b illustrates the expanded graphite agglomerate comprising 20wt% and pulverize, the exfoliated graphite sheet of milling, standard synthetic graphite, carbon black and without the flexural strength of homopolymer polypropylene (PPH, the SabicPP576P) sample of carbonaceous additive and modulus in flexure (ISO178) respectively.

Fig. 7 a and 6b illustrates the data of tensile strength and the tensile modulus (ISO527) obtained for the expanded graphite agglomerate comprising 20wt% pulverizing, the exfoliated graphite sheet of milling, standard synthetic graphite, carbon black and homopolymer polypropylene (PPH, the SabicPP576P) sample without carbonaceous additive respectively.

Fig. 8 a with 8b illustrates compared with the embodiment of the expanded graphite agglomerate of the pulverizing in PPH, comprises longitudinal thermal conductivity of the sample of the expanded graphite powder of 20% pulverizing and horizontal thermal conductivity and mechanical property (flexural strength).

Use the common rotating twin-screw extruder with side feeder for the preparation of Fig. 3 a and 3b, 5, the sample measured of the thermal conductivity shown in 8a and 8b.The expanded graphite with the pulverizing of substantially the same particle diameter is used to carry out the expanded graphite agglomerate of the pulverizing of production sample.After cooling, the line stock (strand) extruded is shredded and injection-molded in water, thus manufacturer's standard tensile strength sample.Cut from tensile strength sample the sample measured for thermal conductivity, and use NetzschTCT416 instrument to measure.

Fig. 9 illustrate for have different tap density agglomerate embodiment three samples tensile strength test after, the cross sectional image of expanded graphite agglomerate sample that fracture PPH/ pulverizes.These images illustrate under high tap density, and agglomerate is not dispersed in PPH preferably.

Figure 10 illustrates the breaking strain measuring result comprising the sample of the embodiment of the expanded graphite agglomerate (having different tap densities) of the pulverizing of 10% at PPH.Use has substantially the same particle diameter (d ₉₀=53 μm) the expanded graphite of pulverizing produce the expanded graphite agglomerate of the pulverizing of two kinds of samples.

Figure 11 describes the shock strength measuring result of the sample of the embodiment of the expanded graphite agglomerate of the pulverizing using the expanded graphite with the pulverizing of different-grain diameter to produce in PPH comprising 20%.The tap density of the expanded graphite agglomerate pulverized is similar (0.14-0.18g/cm ³).

Figure 12 illustrate the pulverizing of being measured by soft vibrosieve according to DIN51938 expanded graphite agglomerate and be greater than 250 μm compression expanded graphite particles embodiment amount between graphics Web publishing.

Figure 13 illustrates in its hardness determined by mechanical water flushing screening according to ENISO787-18:1983, the graphics Web publishing between the result of the embodiment of the expanded graphite agglomerate of pulverizing and the expanded graphite particles of compacting.

Figure 14 illustrates according to DINEN13900 – 5 by strainer die test instrument dispersity in the polymer.Under 5% load, the expanded graphite agglomerate (GEGA sample 2) of the expanded graphite agglomerate (GEGA sample 1) with the pulverizing of <0.4% grit and the pulverizing with 8% hard particulate is mixed in PP(Sabic576P) in and extruded with the strainer of mesh size 150 μm within 15 minutes periods.

To 19, Figure 15 illustrates that the difference of the embodiment of the expanded graphite agglomerate for the preparation of pulverizing of the present invention is arranged and device.

Embodiment

The expanded graphite agglomerate pulverized

The expanded graphite agglomerate (that is, the expanded graphite of granulation or granular pulverizing, at this also referred to as " graphite agglomerate ", " agglomerate " or " particulate ") pulverized has been developed the additive as heat conduction and/or conduction.Inter alia, compared with the expanded graphite of routine, this kind of agglomerate demonstrates the treatment characteristic of improvement and feed performance (particularly when at mixing machine (such as, twin screw extruder mixing machine) in when additive is mixed in polymkeric substance), thus generation has the matrix material of excellent thermal conductivity and electric conductivity and good mechanical property (such as, see Fig. 2 a and 2b, show the favourable feed performance entered in forcing machine).By producing the expanded graphite agglomerate with the pulverizing of adjustable tap density, provide the processing characteristics of improvement, make the expanded graphite agglomerate pulverized be soft, medium hardness or hard thin slice, they being supplied to period in mixing machine and forcing machine, they are free-pouring.

Do not wish by concrete theoretical constraint, should know when adding substrate material to (such as, polymkeric substance) in time, because agglomerate has lower particulate resistance, some embodiment of the expanded graphite agglomerate of pulverizing of the present invention demonstrates less dust, better feed performance and better dispersed, make when be subject to mixing machine or contribute to agglomerate to add with substrate material and the shear stress of any other applicable device of mixing time they are dissolved in polymkeric substance substantially or completely.Therefore shear-stress dissolves agglomerate, thus generates the initial bubble graphite flake (referring to Fig. 2 c) be uniformly distributed in the polymer.As used herein, " initial bubble graphite flake " or " initial bubble powdered graphite " refers to not coalescent or substantially not coalescent expanded graphite, the expanded graphite particles of such as, pulverizing before they are compacted as agglomerate as described in these.

In some embodiments, the expanded graphite agglomerate of pulverizing has scope from about 0.08 to about 1.0g/cm ³, preferably from about 0.08 to about 0.6g/cm ³tap density.Although higher tap density (such as, harder thin slice) usually cause the feed performance of improvement (namely, the maximum output of feeder, again referring to Fig. 2 a) and higher overall yield, higher tap density may have disadvantageous effect to the mechanical property of conductive polymers.Such as, higher tap density can cause expanded graphite less preferably to disperse in the polymer matrix.Therefore, in a specific embodiment, for the improvement ratio between feed performance and dispersiveness in the polymer, the expanded graphite agglomerate of pulverizing has scope from about 0.1 to about 0.4g/cm ³, preferably from about 0.12 to about 0.3g/cm ³, and most preferably from about 0.15 to about 0.25g/cm ³medium tap density.

Should be understood that, the expanded graphite pulverized in practice may not be all coalescent, namely the expanded graphite agglomerate product pulverized is usually by containing a certain amount of non-coalescent (" not coalescent ") particle, if especially this product do not experience can remove from the product obtained less, the final screening step of non-coalescent particle.

In some embodiments, the expanded graphite particles of pulverizing forming agglomerate has by the scope of laser diffraction measurement from about 5 μm to about 500 μm, preferably from about 20 μm to about 200 μm, and most preferably from the median size (d of about 30 μm to about 100 μm ₅₀).In some embodiments, by the d of the expanded graphite of the pulverizing of laser diffraction measurement ₉₀particle size range is from about 10 μm to about 1200 μm.In other embodiments, the d of the expanded graphite of pulverizing ₉₀particle size range is from about 30 μm to about 200 μm.

Can by such as being limited some embodiment of the expanded graphite agglomerate of pulverizing by the characteristic diameter distribution that soft vibrosieve is determined according to DIN51938.Such as, some embodiment of the expanded graphite agglomerate of pulverizing of the present invention is preferably characterised in that size distribution, wherein be retained on the sieve of 250 μm according to 10wt% about in the analysis of DIN51938 to about 80wt%, or approximately 10wt% to about 60wt% is retained on 500 μm of sieves, or approximately 10wt% is retained in 1 mm sieve to about 30wt%, or is less than about 5wt% and is retained in 2 mm sieve.

Some embodiment of graphite agglomerate of the present invention have size range from about 100 μm to about 10mm and preferably from about 200 μm of particulates to about 4mm.In some embodiments, the particle size regimes of agglomerate of the present invention is from about 250 μm to about 1000 μm.Certainly, environmentally, the agglomerate with different size can also be produced.Usually, as explained in more detail below, during the compacting/granulation of some embodiment according to the inventive method, agglomerate size and the density of agglomerate can be regulated by changing some machined parameters.

In a specific embodiment, the agglomerate of at least approximately 10wt% is had on 250 μm of mesh sieves according to DIN51938 graphite agglomerate of the present invention after soft vibrosieve, preferably after soft vibrosieve at least approximately the agglomerate of 25wt% on 250 μm of mesh sieves, and the most electedly, after soft vibrosieve at least approximately the agglomerate of 40wt% on 250 μm of mesh sieves (referring to Figure 12).

The feature of some embodiments of the expanded graphite agglomerate pulverized is that scope is from about 8m ²/ g is to about 200m ²/ g, and preferably from about 12m ²/ g is to about 100m ²/ g, and most preferably from about 15m ²/ g is to about 50m ²/ g than BET surface-area.In other embodiments again, the expanded graphite agglomerate of pulverizing has scope from about 20m ²/ g is to about 30m ²/ g than BET surface-area.

The feature of some embodiment of the expanded graphite agglomerate of pulverizing of the present invention is pellet hardness/softness, when preparing some embodiment of conductive polymers of the present invention, during process agglomerate, its permission is got on coalescent at least substantially, but in most of the cases almost separates coalescent completely.In other words, once be mixed in composite polymeric materials, agglomerate will to a great extent " dissolving ", or to be dissolved into completely in initial bubble graphite granule.

Therefore, in some embodiments, preferably regulate the particle softness of agglomerate, make agglomerate to be supplied in matrix material (such as polymkeric substance) period or afterwards at least about agglomerate of 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95% or 98% be dissolved into median size (d ₅₀) <250 μm particle in.Should be understood that once graphite agglomerate is blended in such as polymkeric substance, be more difficult to determine particle diameter by the particle size measurement procedure of routine.But, such as can see these particles by suitable technology such as laser scanning or SEM imaging.As illustrated in fig. 2 c, this kind of technology allows at least with the particle diameter of expanded graphite particles in semiquantitative mode determination polymkeric substance and distribution.

For determining that in polymkeric substance, the another kind of mode of dispersity is that wherein this instrument is made up of the head and the filter mounting that can add on twin screw extruder with extra pressure transmitter by using strainer die test instrument according to DINEN13900-5.Have the expanded graphite agglomerate of the pulverizing of " grit " of <0.4%, the expanded graphite agglomerate (GEGA sample 2) of pulverizing of " grit " namely staying the particulate (GEGA sample 1) on sieve after mechanical water irrigation tests described herein and have 8% below such as is blended in PP(Sabic576P under 5% load) in and extrude in 15 minutes with the strainer of mesh size 150 μm.The pressure shown from Figure 14 is relative in time diagram, it is clear that the grit existed in GEGA sample 2 does not disperse well during extruding, therefore cause higher pressure, and the GEGA sample 1 with the hard particulate of low amounts does not cause the remarkable increase of pressure in strainer.This shows that soft particulate is easy to by the shearing force dispersion in twin screw device in the polymer, and hard particulate does not disperse well during twin screw mixing.

In some embodiments, pellet hardness increases with the increase of tap density.To have been found that for some polymkeric substance and under particular process condition, higher than about 0.4g/cm ³to about 0.6g/cm ³tap density will no longer cause the abundant solution of polymkeric substance coalescent, result is that the distribution of expanded graphite in polymerizable compound within thing is no longer even, namely this dispersion causing lower solution expanded graphite agglomerate that is coalescent and that pulverize poor in the polymer, forms larger graphite agglomerate agglomerate thus.This kind of embodiment has lower elongation at break (that is, breaking strain declines).In some embodiments, the tap density of agglomerate is regulated to be no more than about 0.3g/cm ³or even about 0.25g/cm ³although should be understood that, the machined parameters that maximum tap density of allowing depends on embody rule and applies when producing polymer composites.

Therefore, in this kind of embodiment, preferably regulate the particle softness of agglomerate, make to be dissolved in the initial expanded graphite particles pulverized agglomerate being supplied in polymkeric substance period most of agglomerate, thus so that the matrix material that manufactures of the expanded graphite that the thermal properties of matrix material and mechanical properties and use are pulverized is same or similar.

But the additional embodiments of graphite agglomerate of the present invention also can be limited by other parameters, these parameters can be determined by standard method before being blended in polymkeric substance by agglomerate.For determining that a kind of applicable test of particulate hardness is the mechanical water washing screen separating tests (referring to Figure 13) according to ENISO787-18:1983.In this test apparatus, will there is dispersion of materials to be tested in water and carry out centrifugal motion by water rotary-jet system.Water rinses fine particle by sieve, and coarse particles and grit are retained on sieve.By dry for the resistates on sieve and weigh.Use 250 μm of order sizes, sieving time that 10g250 μm has graphite agglomerate (they use 250 μm of mesh sieves to use soft vibrosieve to be separated in advance according to DIN51938) to be detected and 10 minutes, be less than about 20%(w/w), preferably be less than about 10%(w/w) or be less than about 5%(w/w), and be more preferably less than about 2%(w/w) the particle of size >250 μm will stay on sieve.In preferred implementation in this aspect of the invention, agglomerate has scope from about 0.15g/cm ³to about 0.20g/cm ³tap density, be wherein less than about 2%, be preferably less than 1% or the particle that is even less than 0.6% be retained on sieve, the size with >250 μm namely as determined in mechanical water washing screen separating tests according to ENISO787-18:1983.

Some embodiments of graphite agglomerate of the present invention can be further characterized in that in gravity dosemeter their maximum output rate, and it is the parameter of the feed performance of reflection composition polymer production period agglomerate material.In some embodiments, in BrabenderFlexWallDDWMD5-FW40Plus-50 gravity dosemeter (BrabenderTechnologieKG of Duisburg, Germany, http://www.brabender-technologie.com), the maximum output of some embodiment of the expanded graphite agglomerate of pulverizing of the present invention is at about 0.125g/cm ³tap density under be at least about 6kg/h and at about 0.25g/cm ³tap density under be at least about 12kg/h.Preferably, maximum output is even higher, such as, at about 0.15g/cm ³tap density under be at least about 8kg/h and at about 0.25g/cm ³tap density under be at least 15kg/h(such as, referring to Fig. 2 a).

Compared with non-particulate expanded graphite meterial, the embodiment of the expanded graphite agglomerate of the pulverizing developed not only has the feed performance of better treatability and Geng Gao, and the characteristic also providing conductive polymers to improve when compared with ordinary graphite additive (referring to, such as Fig. 2 b, 3b, 4,6a and 6b, 7a and 7b).In addition, in some embodiments, observe when the expanded graphite powder of the pulverizing replacing non-compacted form adds agglomerate as described herein, substantially or in fact keep identical (such as, referring to, Fig. 8 a and 8b) by adding the thermal conductivity that provides of expanded graphite meterial and electric conductivity.

In some embodiments, the component that the graphite agglomerate of the present invention at least one that can comprise particle form is other.Usually, before coalescent, multiple additives can be added in the expanded graphite meterial of pulverizing either alone or in combination.In some embodiments, before adding in compound matrix material by mixture, additive can mix with the expanded graphite agglomerate pulverized.Such as natural graphite, synthetic graphite, carbon black, boron nitride, aluminium nitride, carbon fiber, carbon nanofiber, carbon nanotube, Graphene, coke, silver powder, copper powder, alumina powder, steel fiber, PAN, graphite fibre, silicon carbide, Graphene or their combination in the additive that may be used for these objects.The expanded graphite powder pulverized and additional component can mix on the Different Weight mark of relative broad range.Such as, weight ratio can scope from about 95%:5% to about 5%:95%, this depend on the agglomerate obtained object and expection application specific requirement.

In a specific embodiment, the expanded graphite pulverized mixes with other powder (such as natural graphite, synthetic graphite, carbon black, boron nitride, aluminium nitride, carbon fiber, carbon nanofiber, carbon nanotube, Graphene, coke, silver powder, copper powder etc.), then the mixture compacted will obtained, thus obtain the agglomerate containing at least two kinds of different componentss.The advantage of this kind of mixture is the improvement some characteristics of filling substrate material.Such as, the mixture of agglomerate and carbon nanotube, carbon black or fine graphite can improve mechanical property, and the mixture of agglomerate and graphite can reduce wear.In addition, the mixture of agglomerate and boron nitride allows the polymkeric substance of thermal conductivity to be electrical isolation.

For the manufacture of the method for the expanded graphite agglomerate pulverized

The expanded graphite agglomerate pulverized can be prepared by multiple different methods, and some of them will describe in more detail at this.In a specific embodiment, these methods increase the tap density of expanded graphite powder by forming larger agglomerate.Meanwhile, these agglomerate can be enough soft, thus just substantially dissolve once be blended in compound matrix material, thus the excellent performance of initial bubble graphite is passed to the latter's (compound matrix material).In some embodiments; compared with expanded graphite powder; granulating method do not change significantly the expanded graphite agglomerate of the pulverizing obtained than BET surface-area, it shows that the method does not cause the partial destruction (that is, by shear-stress to graphite compacting again) of expanded graphite.

Therefore, provide the method for the expanded graphite agglomerate pulverized for the production of the present invention in another aspect of the present invention, the method comprises the following steps: by expanded graphite agglomerate that is compacted together for the expanded graphite particles of pulverizing thus formation pulverizing.Such as, the expanded graphite compacting will be able to pulverized by drying machinery compacting.Therefore, the method developed is had and is granulated by drying machinery, and does not add additive, provides the advantage of expanded graphite agglomerate or particulate.By selecting concrete compacting parameter, the expanded graphite agglomerate had by the pulverizing of soft, medium or hard laminar different tap density can be produced, the characteristic of hope described herein is provided thus.

In some embodiments, the expanded graphite agglomerate of the pulverizing formed by this debulking methods can have scope from about 0.15g/cm ³to about 0.25g/cm ³tap density.In other embodiments, tap density scope is from about 0.12g/cm ³to about 0.3g/cm ³or from about 0.10g/cm ³to about 0.4g/cm ³.In some embodiments, the size range of the expanded graphite agglomerate of the pulverizing of being produced by said method is from about 0.1mm(100 μm) to about 10mm, although in many cases agglomerate size can from about 200 μm to about 4mm, and preferably from about 250 μm to about 1000 μm.Should be understood that, can regulate by such as extra screening step after compaction or finely tune particle diameter and the size distribution of the hope of agglomerate.

By carrying out compacting after a grinding step, likely in the Different Weight mark of relative broad range, other powder of expanded graphite and at least one pulverized are mixed (such as natural graphite, synthetic graphite, carbon black, boron nitride, aluminium nitride, carbon fiber, carbon nanofiber, carbon nanotube, Graphene, coke, silver powder, copper powder or their combination) alternatively, this blend of compacting subsequently, so that the agglomerate obtaining containing different powder.The advantage of this kind of mixture is some characteristic improving matrix material potentially.Such as, the mixture of agglomerate and carbon nanotube, carbon black or fine graphite can improve mechanical property, and the mixture of agglomerate and extra graphite can improve the lubricity of polymer compound.In addition, the mixture of agglomerate and boron nitride allows the polymkeric substance of thermal conductivity to be electrical isolation.Weight ratio can widely change, and scope is such as from about 95%:5% to about 5%:95%(w/w), although likely or be even necessary that some additive only adds up to about 5%(w/w) even less, such as, up to about 4%, about 3%, about 2% or about 1% of the expanded graphite quality pulverized.In some embodiments, % weight ratio (expanded graphite of pulverizing: other powder) is 90:10,80:20,70:30,60:40,50:50,40:60,30:70,20:80 or 10:90.

Can in the field adopting particulate matter usually many differences of equipment that are known and that use realize the compacting of the expanded graphite meterial pulverized in arranging, although and unnecessary be graphite.In fact, as described below, many publications and patent document disclose the method and apparatus be applicable to for compacted powder form material.

J.R.Johanson, " Arollingtheoryforgranularsolids " JournalofAppliedMechanicsSeriesE32,842-848,1965, describe the theoretical model developed in roller compaction, it can from the surface pressure of the size prediction cylinder of the physical properties of powder and cylinder, moment of torsion and separating force.A.Falzoneetal., " EffectofChangesinRollerCompactorParametersonGranulations ProducedbyCompaction ", DrugDevelopmentandIndustrialPharmacy18 (4), 469-489,1992, have studied compactor parameter, drum speed, horizontal feed speed and vertical speed of feed to the impact of Product characteristics.Author finds that horizontal feed speed and the change of drum speed on granulation feature have maximum impact.

Z.Drzymala, " Researchintothebriquettingprocessforimproveddesignofbriq uettingmachines ", Materials & Design15 (1), 33-40,1993, discuss the mathematical model of the roller compaction process describing fine particle materials.

S.G.vonEggelkraut – Gottankaetal., " RollerCompactionandTablettingofSt.John'sWortPlantDryExtr actUsingaGapWidthandForceControlledRollerCompactor.I.Gra nulationandTablettingofEightDifferentExtractBatches ", PharmaceuticalDevelopmentandTechnology7 (4), 433-445,2002, have studied the impact of compacting parameter on the particle mass of dry medicinal herbal extract.P.GuionandO.Simon, " Rollerpressdesign-influenceofforcefeedsystemsoncompactio n ", PowderTechnology130,41-48,2003 describe the design of many different drum pressures, and machine parameter is discussed in the interaction concentrated between recognition machine parameter and compaction quality.

K.SommerandG.Hauser, " Flowandcompressionpropertiesoffeedsolidsforroll-typepres sesandextrusionpresses ", PowderTechnology130,272-276,2003, describe in detail and different parameters is discussed on the theoretical background of the Roller compaction of the impact of product property.L.Grossmannetal., " EmpiricalStudyoftheCompactionofCohesiveBulkSolidsinaRoll Press ", Aufbereitungstechnik47 (6), 22-29,2006, have studied the impact of compacting in machine parameter pair roller type press, and detect parameters is pressure and the rotating ratio between feed screw and cylinder.

The survey article " Systematicalapproachofformulationandprocessdevelopmentus ingrollercompaction " of the people such as Y.Teng, EuropeanJournalofPharmaceuticsandBiopharmaceutics73,219-229,2009, concentrate on the roller compaction of medicine.Correlation parameter is confirmed as compaction force, drum speed and feeder screw speed.At G.Reynoldsetal., " Practicalapplicationofrollercompactionprocessmodeling ", ComputersandChemicalEngineering34,1049-1057, in 2010, author describes different machines parameter, roller pitch, drum speed, drum pressure, screw speed to the impact of density of particle, and the difference between model and observed data.

EP0310980B1(K.Werneckeetal., AlexanderwerkAG(DE)) describe use roller press for being produced the method for block compacting material by the gas gypsum of fine dispersion.Similarly, EP1230004(A.Eggert, AlexanderwerkAG(DE)) relate to the debulking systems of the loose material for being supplied to roller press via feed screw.This system is also the embodiment of the graphite agglomerate material of compacting for the production of some embodiment of the present invention.

Therefore, exist in this area usually about coalescent the enriching one's knowledge of solid material, comprise the parameter affecting particle properties, such as particle diameter, shape and pellet hardness.The many illustrative methods for the manufacture of the expanded graphite agglomerate pulverized and device are described in more detail below.

For the manufacture of the illustrative embodiment of the embodiment of the expanded graphite agglomerate pulverized

In some embodiments, compacting step (that is, coalescent) can realize by using the method for roller compactor.Such as, the device be applicable to is the roller compactor PP150 manufactured by the AlexanderwerkAG of Remscheid, Germany.In this approach, the tap density (for two kinds of different arranging respectively referring to Figure 15 and 16) by regulating delivery rate, cylinder gap and mesh size to obtain hope.Preferably, the expanded graphite particles pulverized under the help of spiral is sent on the cylinder of a pair reverse rotation, thus produces pre-coalescence body, and and then a fine agglomerate step, is forced through sieve by pre-coalescence body thus, and this helps to limit the agglomerate size of wishing.

In an alternative embodiment, as described in DE-OS-3432780A1, undertaken coalescent by using the method for Flat die cuber.In this approach, tap density is regulated by the speed of the gap between cylinder, mould and die size and rotating knife.Preferably, by disc type barreling machine cylinder, the expanded graphite particles of pulverizing is pressed through mould, and then with proper method such as rotating knife, the graphite granule of pre-coalescence is cut into the size (referring to Figure 17) of hope.

In another ad hoc approach embodiment again, undertaken coalescent (referring to Figure 18) by adopting the method for pin mixer-granulator or rotary drum nodulizer.Several patent describes these granulator system for coalescent dissimilar powder, such as US3, and 894,882, US5,030,433 and EP0223963B1.In the variant of these methods, regulate tap density respectively by the selection of delivery rate, moisture content, additive and the rotating speed of concentration and pin rotating shaft or rotary drum.

In another alternate embodiments again of present method, by bed process, realize coalescent (referring to Figure 19) by spray-dryer method or by fluid bed spray dryer method.

Bed process for the preparation of some embodiment of agglomerate of the present invention can use the instrument of several patent such as described in DE19904657A1 and DE10014749B4 (for coalescent/be granulated different powder) implement.The spray-dryer method be applicable to can utilize CH359662, US7, the instrument (again for being granulated different powder) described in 449,030B2, EP0469725B1 and JP4113746B2.Finally, such as EP1227732B1, EP0729383B1 and WO01/03807A1 describe (for being granulated different powder, but not being graphite) applicable fluid bed spray dryer, and it may be used in Agglomeration methods disclosed herein.

In embodiment part, exemplary method is described in more detail below.

In some embodiments in this aspect of the invention, method for the preparation of the embodiment of agglomerate of the present invention comprises grinding expanded graphite meterial further, to form the expanded graphite particles pulverized, compacting/agglomeration step can be used it for subsequently.This kind of embodiment of present method starts to supply expanded graphite, then by expanded graphite grinding or the size distribution being milled into hope.

In some embodiments, expanded graphite can be milled by air, certainly be milled or mechanical disruption.In a specific embodiment, grinding expanded graphite makes expanded graphite layering at least partially or destroys the vermiform surface shape of expanded graphite, or their combination.In some embodiments, expanded graphite can be pulverized to have the median size (d of scope from about 5 μm to about 500 μm ₅₀), although d in many cases ₅₀can scope from about 20 μm to about 200 μm, or even scope from about 30 μm to about 100 μm or about 20 μm to about 50 μm.In some embodiments, the d of the expanded graphite of pulverizing ₉₀particle size range is from about 10 μm to about 1200 μm.In other embodiments, the d of the expanded graphite of pulverizing ₉₀particle size range is from about 20 μm to about 500 μm or from 30 μm to about 200 μm.

In other embodiments in this aspect of the invention, the method comprises further prepares expanded graphite by any applicable method known in the art from natural and synthetic graphite material.Such as, alternatively by such as using acid (as such as H ₂sO ₄or HNO ₃) and oxygenant (such as, hydrogen peroxide H ₂o ₂, or ammonium sulfate compound such as ammonium persulphate NH ₄s ₂o ₈, or potassium permanganate KMnO ₄) mixture vacuum impregnation process native purified graphite flake, until these compound penetration insert in the graphite flake of crystal structure of graphite between graphite linings.After filtering and rinse the graphite inserted, at the temperature of the decomposition temperature higher than Insertion compound, (described temperature is generally the temperature higher than about 600 to about 700 ° of C, and be preferably about 1000 ° of C) under inert atmosphere or reducing atmosphere, heat acid-treated graphite, thus obtain (exfoliated) graphite material that is that expand or that peel off.

In some embodiments, the thermal expansion graphite being in its its vermicular form (vermicularform) is used.As used herein, state " being in the thermal expansion graphite of its its vermicular form " or " vermicular expanded graphite " and refer to the expanded graphite form being in its vermicular form surface shape and directly obtaining after thermal expansion.Particularly, it refer to vermicular expanded graphite be in thermal expansion after its natural form of directly obtaining.When fully expanding on its crystal c axle of its initial z dimension, thermal expansion graphite has vermiform surface shape, i.e. Z sample (accordion-like) or worm sample (worm-like) structure.

It should be noted that, particle diameter and particle shape do not indicate the graphite that there is vermiform surface shape.The texture of expanded graphite clearly illustrates that vermiform surface shape just.Because the method is based on spheroidal particle, cause the height tolerance with actual particle size when the material such as expanded vermicular graphite of high anisotropy by laser diffraction determination size distribution.Can by identifying its vermicular form of expanded graphite perpendicular to the turgidity of original graphite material on the crystallization c direction of graphene layer.Thermal expansion produces the remarkable increase perpendicular to the z dimension of the graphite granule of graphite granule plane.Usually on the crystallization c direction of Z sample (accordion-like) surface shape providing its vermicular form, this expansion causes the remarkable minimizing of tap density and the remarkable increase than BET surface-area.

In some embodiments, for the formation of the primary particles turgidity of vermiform surface shape can be at least 80 times of the z dimension of non-Expandable graphite sheet.In other embodiments, Expandable graphite sheet initial bubble degree is in z-direction in the scope of 200 to 500 times of its initial Z dimension.

For the additive of matrix material such as conductive polymers

the expanded graphite agglomerate additive pulverized

The expanded graphite agglomerate of pulverizing as described herein can be used as the additive producing matrix material (such as conductive polymers, pottery, inorganic materials or material of construction).The conductive polymers of the expanded graphite agglomerate comprising pulverizing can be produced, there is less feed performance issue (that is, producing high yield) and for multiple application, there is suitable thermal conductivity and electric conductivity.

the expanded graphite particles additive of compacting

In an alternative embodiment, provide the additive for the preparation of conductive polymers, it contains the expanded graphite particles of compacting.

By providing expanded graphite, by expanded graphite compacting or large size article can be molded as (such as, exfoliated graphite sheet as known in the art), then grind molded expanded graphite article, shred or be milled into the particle of the expanded graphite of compacting thus prepare the expanded graphite particles of the compacting of conductive polymers additive.

Thus, difference between this kind of " expanded graphite particles of compacting " from " the expanded graphite agglomerate of pulverizing " is not only presented at tap density different (" expanded graphite particles of compacting " is larger usually), and be presented in the hardness of bi-material, wherein " the expanded graphite agglomerate of pulverizing " is softer.

The amount being greater than often kind of material of 250 μm can assign to determine (referring to Figure 12) by soft vibratory screening apparatus according to DIN51938: the material obtained by the thin slice grinding expanded graphite primarily of the material composition being greater than 250 μm, and has the agglomerate (although usually increasing with the increase of tap density) being greater than 250 μm of small amount by the material that the expanded graphite that compacting is pulverized obtains.In some embodiments, mechanical water rinses the expanded graphite agglomerate of screening pulverizing (as obtained by soft vibrosieve, its have be greater than 250 μm of sizes) cause the agglomerate being less than about 5wt% to be retained on 250 μm of sieves, this shows the less particle of softness " dissolvings " one-tenth of graphite granule in this test.On the contrary, some embodiments of the expanded graphite particles of the compacting of screening are rinsed (namely for standing mechanical water, as what obtained by soft vibrosieve, there is the chopping thin slice being greater than 250 μm of sizes), due to its hardness, be retained on 250 μm of sieves more than about 80wt%.Usually, the size of the expanded graphite particles of compacting is similar to for observed by graphite agglomerate of the present invention.Therefore, the size of particle can scope from about 0.1mm(100 μm) to about 10mm, although in most cases agglomerate size can from about 200 μm to about 4mm, or from about 250 μm to about 1000 μm.

Matrix material

Present invention also offers the matrix material comprised as the expanded graphite agglomerate of said pulverizing or some embodiment of conductive polymers additive.

In some embodiments, matrix material comprises the substrate material comprising polymeric material, stupalith, inorganic materials, paraffin or material of construction.In a specific embodiment, these matrix materials may be used for the material preparing heat conduction and/or conduction.Exemplary material comprise such as LED luminescent material, solar panel, electronic installation (it helps heat dissipation) or underground heat flexible pipe, wherein conductive polymers as heat exchanger floor heating (usually in a heat exchanger (such as, for automobile application)), based on salt (such as, position becomes material or low melting point salt) hot storage system, thermal conductivity pottery, abrasives, cement, gypsum or clay (brick such as, for building) for brake facing, thermostatted, graphite bi-polar plate or carbon brush.The polymeric material being suitable for conductive polymers comprises such as polyolefine (such as, polyethylene is LDPE, LLDPE, VLDPE, HDPE such as, and polypropylene is homopolymer (PPH) or multipolymer, PVC or PS such as), polymeric amide (such as, PA6, PA6,6; PA12; PA6,10; PA11, aromatic poly amide), polyester (such as, PET, PBT, PC), vinylformic acid or acetic ester/salt (such as, ABS, SAN, PMMA, EVA), polyimide, sulphur/ether polymer (such as, PPO, PPS, PES, PEEK), elastomerics (natural or synthetic rubber), thermoplastic elastomer (such as: TPE, TPO), thermosetting resin (such as, resol or epoxy resin), their multipolymer or the mixture of any above-mentioned materials.

The duty ratio of the expanded graphite agglomerate pulverized generally can change widely, and this depends on the target value desired by thermal conductivity and the requirement in the mechanical stability of composite polymer.In some embodiments, by adding about 3% to about 5%(w/w) obtain good result, although the weight ratio of adding graphite in most applications may be slightly high, such as about 10%, about 15%, about 20%, about 25% or about 30%(w/w).But, do not get rid of conductive polymers in other embodiments and contain the expanded graphite even exceeding about 30%, such as about 40%, about 50%, about 60% or even about 70%(w/w).In some embodiments of conducting polymer composite material, as carbon brush or bipolar plates, use even approximately 80%(w/w) or about 90%(w/w) the load of graphite agglomerate.

Under any circumstance, if the electric conductivity of polymkeric substance is also wish, the concentration of graphite in final polymkeric substance can be regulated to exceed so-called percolation threshold ratio, fall than the usual index underground of the resistivity of polymkeric substance higher than this threshold value.On the other hand, should consider, the melt flow index of matrix material reduces significantly along with the increase of content of graphite in polymkeric substance.Therefore, the content of graphite in composite polymer blend also depends on the peak viscosity of allowing in molding process.But melt flow index can also depend on the selection of polymer type.

In some embodiments, as shown in fig. 3a, the expanded graphite agglomerate that the present invention pulverizes such as can be used as the heat conduction additive in homopolymer polypropylene (PPH).The low heat conductivity (about 0.4W/m*K) of the PPH of pure (" purely ") is with the about 20%(w/w of expanded graphite agglomerate load pulverized) under under lower fill level (about 3.5W/m*K) order of magnitude can be increased.Horizontal thermal conductivity is the only about half of of longitudinal thermal conductivity.These results show during injection-molded process due to they alignment, in finalization compound, show the anisotropy of expanded graphite particles.When designing the material of some embodiment using conductive polymers described herein, this characteristic should take in, and even may be used for finely tuning final thermal conductivity.Certainly, the orientation (direction) of sample during thermal conductivity not only depends on measurement consumingly, and depend on the type of polymkeric substance, sample history (type of mixing and processing and condition) and measuring method.

Especially, feed performance and process (handling) performance of the improvement of the expanded graphite agglomerate of pulverizing can be obtained, and do not sacrifice the thermal characteristics of expanded graphite and the mechanical property of polymer compound, namely the thermal conductivity obtained for blend polymer is substantially or identical in fact, no matter uses the expanded graphite of Graphite Powder 99 or coalescent pulverizing.As shown in figs. 8 a and 8b, containing 20%(w/w) thermal conductivity of the polymeric blends of the expanded graphite agglomerate of the expanded graphite pulverized and pulverizing and mechanical property be actually comparable.

About the mechanical property of conductive polymers, observed in some cases, the modulus of elasticity of conductive polymers, tension force and bending strength increase with the concentration of the expanded graphite agglomerate pulverized and increase.In other cases, the breaking strain of conductive polymers and shock strength increase with the concentration of the expanded graphite agglomerate pulverized and reduce.In other embodiments again, the E-modulus of conductive polymers and breaking strain increase with the tap density of the expanded graphite pulverized and reduce.Such as, if the expanded graphite agglomerate of compacting is really up to the mark, they can not be dissolved completely in polymkeric substance, and may have a negative impact (see Fig. 9 and 10) to the machinery of polymkeric substance and/or transport properties.

In other embodiments, shock strength increases with the reduction of the size distribution of initial bubble graphite, in conductive polymers, therefore provide stronger mechanical property (see Figure 11).

Due to unexpansive graphite-phase ratio, the expanded graphite agglomerate of pulverizing can be issued to the target value of thermal conductivity in lower load, it suitably can keep good mechanical properties and the rheological property of composite polymer.

For the preparation of the method for conductive polymers

Present invention also offers the method for some embodiment for the manufacture of conductive polymers of the present invention.The method comprises the expanded graphite agglomerate pulverized as described herein or conductive polymers additive is supplied to (such as twin screw extruder in hybrid machine, single screw extrusion machine, kneader altogether, internal mixer (internalmixer) or long-time continuous mixing machine), mixed polymer and agglomerate thus, and then the conductive polymers mould process obtained is become (such as, injection mo(u)lding, compression molded, injection compression molding, extrude, film blowing, thermoforming, casting, extrusion-blown modling is molded, injection blow molding is molded, rotate, RIM, RTM, pultrusion, inducing action, emulsifying effect, transmit injection (transfermoulding), rotating blow is molded, transmit molded (transfermoulding), injection is transmitted molded (injectiontransfermoulding), calendering (calendaring) or bubble) form of wishing.

The use of conductive polymers

Finally, the invention still further relates to the purposes using the embodiment of conductive polymers of the present invention for the preparation of heat conduction and/or conducting polymer materials.Such as, exemplary material comprises LED luminescent material, solar panel, electronic installation (help heat dissipation and for cover), usually wherein conductive polymers is used as heat exchanger (such as, floor heating is applied, interchanger in automobile application, heat abstractor) underground heat flexible pipe, packing ring and hot interface, packaging system, trolley part under bonnet, the encapsulation of engine, ventilation part, for the cell box of electric vehicle, for brake facing abrasives (such as, based on resin), thermostatted, graphite bi-polar plate, or carbon brush (such as, based on polymkeric substance such as thermoplastic resin or thermosetting resin).

Compared with being generally used for the metal group material of the application wherein needing thermal conductivity, the advantage of conductive plastics comprises compared with usually quite expensive metal group material, adds the degree of freedom of designing material, material weight lighter and save cost.

Measuring method

Unless otherwise, otherwise herein means fixed per-cent (%) value and be by weight.

bET specific surface area

The method be according under 77K at scope p/p ₀the record of the isothermal adsorption of liquid nitrogen in=0.04-0.26.According to Brunauer, Emmet and Teller(AdsorptionofGasesinMultimolecularLayers, J.Am.Chem.Soc., 1938,60,309-319) method that proposes, can monolayer capacity be determined.According to the cross-sectional area of nitrogen molecule, the monolayer capacity of sample and weight, then can calculated specific surface area.

tap density

Dry for 100g Graphite Powder 99 is poured in graduated cylinder carefully.Subsequently, graduated cylinder is fixed on the plain bumper (tappingmachine) of eccentrically weighted shaft class, and runs 1500 strokes.Obtain volume reading and calculate tap density.

Reference :-DIN-ISO787-11

by the size distribution of laser diffraction

In coherent light beam, there is particle cause diffraction.The size of diffraction pattern is relevant with particle diameter.Collimated beam from low power laser lights the cell containing the sample be suspended in water.The light beam leaving this room is focused on by optical system.The distribution of luminous energy in the focussing plane of then analytical system.By counter, the transform electrical signals provided by fluorescence detector is become size distribution.The small sample of graphite mixes with several wetting agents and a small amount of water.The sample prepared in this way to be introduced in the storage receptacle of instrument and to measure.

Reference :-ISO13320-1/-ISO14887

by the size distribution of soft vibrosieve

Usually, assembling has one group of circular sieve of the mesh size reduced gradually and is fixed on bobbing machine.The dry powder of 50g is poured on the top (=minimum sieve number) of sieve.By this group vibration certain hour, and the resistates of sieve above and in chassis is weighed and calculated size distribution.In order to be determined the particle diameter of agglomerate of the present invention by soft vibrosieve, use the analysis screen vibrator with one 250 μm sieves (60 order) aS200.Be set to amplitude 1.03, time length 5min, within every 13 seconds, interrupt (being called interval) and carry out each test by the expanded graphite agglomerate that 50g pulverizes.

Reference: DIN51938

mechanically water rinses screening

In this testing method, according to DINENISO787-18:1983, the 10g agglomerate (from the resistates of soft vibrosieve on 250 μm of sieves) be dispersed in water carries out circus movement by water spray (having the pressure of the 300 ± 20kPa) rotor being positioned at container.By water from coarse particulate material separate fine particles material and fine particle is flushed through sieve continue at least 10 minutes, to smash agglomerate.To sieve the dry 1h of resistates under 105 ± 2 ° of C, in loft drier, cooling is sieved and is weighed into closest to 0.1mg.

thermal conductivity

Several heat analysis methods can the thermal conductivity of measure sample (solid, liquid or powder), is the function of temperature.Such as, NetzschTCT416 thermal-analysis instrumentation (sample size: up to 5x5x35mm, useful range: 0.5-250W/mK) can be used to carry out measurement.

Design the thermal conductivity that thermal conductivity tstr NetzschTCT416 is used for measuring solid, scope is λ=0.5 to 250Wm ^-1k ^-1, accuracy is ± 5%.Therefore, the plastics of low electrical conductivity and high conductivity material can be tested as graphite, metal and alloy with NetzschTCT416.(average test specimen temperature) thermal conductivity measurement can be carried out in the temperature range of 30 to 60 ° of C.

This test relates to following steps: heat is via heat block (T _h) be fed into the lower front side of rod test specimen.Rod test specimen is by constant temperature T _u(T _u<T _h) around.Usual heat block is set as the temperature T of 60 ° of C _hand be 25 ° of C(T around block _u).The heat trnasfer of dealing test specimen is guaranteed by conductive paste and by the load (normally 25N) be applied on test specimen.When equilibrium is reached (usually for λ >100Wm ^-1k ^-15-10min and for λ ~ 20Wm ^-1k ^-1after 15-20min), the temperature T of the rod rear surface of test specimen is measured by two thermopairs (type K, NiCr-Ni) ₂with the temperature T of its rod upper end face ₁.Can from temperature T ₁and T ₂calculate thermal conductivity (TC), this depends on the heat transfer coefficient between the thermal conductivity of test material and test specimen and its environment.The temperature measured also depends on the geometrical dimension of test specimen.Can this be used to test on the rod member having 6mm rounded section or have a 5x5mm square cross section.The length of test specimen depends on the TC of material: for λ >5Wm ^-1k ^-1for 35mm and for λ <5Wm ^-1k ^-1for 20mm.End surfaces should be parallel and perpendicular to side, and very level and smooth, to provide good heat trnasfer.Before must calibrating, the size deviation of ± 0.3mm is acceptable again.

Measure: before the start of the measurement by two cuts, 2 hours (T _h=60 ° of C, T _u=25 ° of C), to reach steady state (temperature contrast is lower than 0.1 ° of C).Carry out twice measurement, between twice measurement, sample is overturn.Thermal conductivity is the median of two values.

Calibration: the calibration carrying out TCT416 on four with two kinds of different length (20 and 35mm) different reference pieces (referring to table 1), to determine calibration factor.For each reference piece, replicate measurement three times and median are used for calibration.Annual or recalibration after 20 times are measured.

Form 1: the characteristic of reference material

Alternatively, the thermal conductivity of polymkeric substance is determined, such as, at AnterQuickline by shielded thermal flow meter method (ASTME1530) ^tMin-10 instruments (sample size: disk Φ 50mm, up to 30mm thickness, useful range: 0.1-20W/mK).

The thermal conductivity of polymkeric substance can also be determined by Laserflash method (ASTME-1461), such as, from the LFA447 instrument of Netzsch.

izod impact strength (Izodimpactstrength)

According to ISO180:1993(E) use the Ceast6545 shock-testing machine of the multiple pendulum being equipped with different-energy (1,2.75 and 5J) to measure the measured value of unnotched Izod impact strength.The absorption of measuring from ten samples of the sample of each supply can (J), shock strength (kJ/m ²) and shock strength (J/m).Absorb can (W) should between the pendulum energy (E) of 10% to 80%, otherwise pendulum must change.If possible, use the pendulum with highest energy always.

breaking strain

According to BS2782: part 3: method 320B uses the TiniusOlsenH10KS tonometer being equipped with 10KN load cell (loadcell) to measure the measured value of the tensile property of supplied sample.The yielding stress (MPa) of ten samples of each supply sample (Class1 test specimen), rupture stress (MPa) and breaking strain (%) is measured with the separation rate of 50mm/min.Use and be set as that the mechanical elongation instrument of 70mm gauge length is to measure elongation.

It will be clear for those skilled in the art that may there is many amendments and small change and without departing from the spirit and scope of the present invention.Only as explanation, illustrative embodiments of the present invention is described referring now to following examples.

Embodiment

Embodiment 1-is used for the Agglomeration methods of expanded graphite

In order to prepare the expanded graphite agglomerate of pulverizing, under the help of spiral, the expanded graphite initially pulverized is supplied on the cylinder of a pair reverse rotation.By making expanded graphite by cylinder by its pre-coalescence.In this embodiment, the cylinder (although cylinder can also have structurized surface, to improve productive rate) with smooth surface is adopted.In the second step (fine agglomerate step), under the help rotating clamping plate, the expanded graphite of pre-coalescence is forced through final sieve or the group of sieve, this helps the agglomerate size (see Figure 15) limiting the expanded graphite pulverized.By the tap density suitably selecting the gap between helix speed, cylinder and mesh size to regulate hope, thus produce the soft agglomerate (the roller compactor PP150 manufactured by the AlexanderwerkAG of Remscheid, Germany) of the hope of the expanded graphite pulverized.

Illustrate in the following table cylinder gap parameters on product feature (tap density, by the size distribution of vibratory screening apparatus and water sieve and obtain the BET surface-area of agglomerate) impact:

Form 2: cylinder gap is on the impact of Product characteristics

Embodiment 2-is used for the alternative Agglomeration methods of expanded graphite

In alternative setting, use the machine with different geometry arrangement to manufacture the agglomerate of the expanded graphite of pulverizing.In this is arranged, as shown in Figure 16, under the help of vertical spin, raw material vertically delivers to (PowtecRC210 manufactured by the PowtecMaschinenundEngineering company of Remscheid, Germany) on the cylinder of reverse rotation.Again tap density is regulated by helix speed, cylinder gap and final mesh size.

Embodiment 3-is used for the alternative Agglomeration methods of expanded graphite

pin mixing tank method of granulating

In alternative method, production agglomerate can be carried out by the pin mixing tank granulator system that this area is usually known.Such as, this kind of pin mixing tank granulator system is widely used in coalescent carbon black powders.Pin mixing tank is by cylindrical stable housing and be equipped with the turning axle of pin to form.The expanded graphite of initial pulverizing enters system in one end of cylinder, and when it moves from entrance, can be lashed (whip) by rotating dog, arrives outlet at bottom by housing.Can in the fine particle spraying of import section adding liquid or steam, and throughout whole powder dispense, this causes the meticulous mixing of particle and micro-coalescent.In this embodiment, liquid or steam can be water, although usually in this is arranged any inert liq can work.And, can additive be added in this stage.

This method can need the second drying step, to remove moisture from the expanded graphite agglomerate pulverized.The tap density of agglomerate can be regulated by delivery rate, moisture content, the type of additive of adding and amount and pin rotating shaft rotating speed.

Embodiment 4-is used for the alternative Agglomeration methods of expanded graphite

rotary drum method of granulating

In this approach, rotary drum granulator system can be used to realize coalescent, described rotary drum granulator system is very similar to the pin mixing tank described in embodiment 4 usually.At this, can the expanded graphite of pulverizing be equipped with in the rotating cylinder of pin, blade or cone, shift material onto outlet from the entrance of rotary drum thus.Wetting liquid can be sprayed in this cylinder.Then other drying step can be used, to remove moisture from agglomerate.

The tap density of the expanded graphite agglomerate of pulverizing can be regulated by delivery rate, moisture content, the selection of additive added and amount and rotary drum rotating speed.

Embodiment 5-is used for the alternative Agglomeration methods of expanded graphite

fluidized-bed Agglomeration methods

Such as described in DE19904657A1 or DE10014749B4, another alternative method for the preparation of the expanded graphite agglomerate pulverized can adopt fluid-bed chamber.The expanded graphite initially pulverized can be supplied to fluid-bed chamber inlet region.The treatment stage of can technique gas being supplied to all below fluidized-bed.By spraying or water and tackiness agent can be introduced by injection stream above fluidized-bed.Whole composition can be fluidized thus form the homogenizing particulate of the expanded graphite pulverized.

Embodiment 6-is used for the alternative Agglomeration methods of expanded graphite

spray-dryer Agglomeration methods

In this approach, the expanded graphite agglomerate of pulverizing can be prepared by spraying dry.The spray-drying apparatus of the agglomerate for the preparation of different powder has been described, such as CH359662, US7,449,030B2, EP0469725B1 and JP4113746B2 in several patent.

Aqueous-based dispersions containing the initial expanded graphite particles pulverized and alternatively tackiness agent can be atomized thus form small droplets, and by air-flow vaporised liquid, thus coalescent Graphite Powder 99.The agglomerate that can be formed at the bottom collection of spray-dryer instrument, and subsequent drying, to remove residual moisture.

Embodiment 7-is used for the alternative Agglomeration methods of expanded graphite

fluid bed spray dryer Agglomeration methods

Fluid bed spray dryer method for the manufacture of coalescent expanded graphite forms by conjunction with two methods described in preceding embodiment 6 and 7.The aqueous-based dispersions (containing additive alternatively as tackiness agent) of the expanded graphite of initial pulverizing can be atomized into the top that small droplets Central places enters kiln, wherein can introduce dry gas thus small droplets is partly dried to moist particle, and they are carried to by the direction broadened downwards bottom, fluidized particles bed can be formed by fluidizing agent to upper reaches stock at this, thus dry, classification and coalescent particle wherein.

Claims (39)

1. a graphite agglomerate, comprises the expanded graphite particles of pulverizing compacted together.

2. graphite agglomerate according to claim 1, wherein said agglomerate is in size range from 100 μm to the granular form of 10mm.

3. graphite agglomerate according to claim 1, wherein said agglomerate is in size range from 200 μm to the granular form of 4mm.

4. graphite agglomerate according to claim 1, has from 0.08 to 1.0g/cm ³tap density.

5. graphite agglomerate according to claim 1, has from 0.08 to 0.6g/cm ³tap density.

6. graphite agglomerate according to claim 1, has from 0.12 to 0.3g/cm ³tap density.

7. graphite agglomerate according to claim 1, the expanded graphite particles of wherein said pulverizing has the median size d from 5 μm to 500 μm ₅₀.

8. graphite agglomerate according to claim 1, the expanded graphite particles of wherein said pulverizing has the median size d from 20 μm to 200 μm ₅₀.

9. graphite agglomerate according to claim 1, the expanded graphite particles of wherein said pulverizing has the median size d from 30 μm to 100 μm ₅₀.

10. the graphite agglomerate according to any one of claim 1 to 9, wherein after soft vibrosieve, at least the described agglomerate of 10wt% is retained on 250 μm of mesh sieves.

11. graphite agglomerate according to any one of claim 1 to 9, wherein after soft vibrosieve at least the described agglomerate of 25wt% on 250 μm of mesh sieves.

12. graphite agglomerate according to any one of claim 1 to 9, wherein after soft vibrosieve at least the described agglomerate of 40wt% on 250 μm of mesh sieves.

13. graphite agglomerate according to any one of claim 1 to 9, have from 8m ²/ g to 200m ²/ g than BET surface-area.

14. graphite agglomerate according to any one of claim 1 to 9, have from 15m ²/ g to 50m ²/ g than BET surface-area.

15. graphite agglomerate according to any one of claim 1 to 9, wherein according to ENISO787-18:1983, under 250 μm of order sizes and 10 minutes sieving times, when the agglomerate standing mechanically water washing screen timesharing and be less than after soft vibrosieve 20%w/w is retained on described 250 μm of mesh sieves.

16. graphite agglomerate according to any one of claim 1 to 9, wherein according to ENISO787-18:1983, under 250 μm of order sizes and 10 minutes sieving times, when the agglomerate standing mechanically water washing screen timesharing and be less than after soft vibrosieve 10%w/w is retained on described 250 μm of mesh sieves.

17. graphite agglomerate according to any one of claim 1 to 9, wherein according to ENISO787-18:1983, under 250 μm of order sizes and 10 minutes sieving times, when the agglomerate standing mechanically water washing screen timesharing and be less than after soft vibrosieve 2%w/w is retained on described 250 μm of mesh sieves.

18. graphite agglomerate according to any one of claim 1 to 9, the maximum output of the expanded graphite agglomerate wherein pulverized described in BrabenderFlexWallDDW-MD5-FW40Plus-50 gravity dosemeter is at 0.125g/cm ³tap density under be at least 6kg/h and at 0.25g/cm ³tap density under be at least 12kg/h.

19. graphite agglomerate according to any one of claim 1 to 9, wherein said agglomerate comprises the other component of at least one of particulate form.

20. graphite agglomerate according to claim 19, the expanded graphite of wherein said pulverizing relative to the weight ratio of described other components of at least one from 95:5 to 5:95.

21. graphite agglomerate according to claim 19, wherein said other component is selected from by the following group formed: natural graphite, synthetic graphite, carbon black, boron nitride, aluminium nitride, carbon fiber, carbon nanotube, coke, silver powder, copper powder, alumina powder, steel fiber, PAN, graphite fibre, silicon carbide, Graphene or their combination.

22. graphite agglomerate according to claim 21, wherein said carbon fiber is carbon nanofiber.

23. 1 kinds for the manufacture of any one of claim 1 to 22 the method for the expanded graphite agglomerate of pulverizing that defines, the expanded graphite particles comprised pulverizing is compacted together, thus forms the expanded graphite agglomerate of described pulverizing.

24. methods according to claim 23, wherein said compacting step comprises compacting together with the expanded graphite particles of described pulverizing and the other component of at least one of particulate form, thus produces the expanded graphite agglomerate pulverized.

25. methods according to claim 24, the expanded graphite of wherein said pulverizing relative to the weight ratio of described other components of at least one from 95:5 to 5:95.

26. methods according to claim 24, wherein said other component is selected from by the following group formed: natural graphite, synthetic graphite, carbon black, boron nitride, aluminium nitride, carbon fiber, carbon nanotube, coke, silver powder, copper powder, alumina powder, steel fiber, PAN, graphite fibre, silicon carbide, Graphene or their combination.

27. methods according to claim 26, wherein said carbon fiber is carbon nanofiber.

28. methods according to any one of claim 23 to 27, wherein said coalescent by being selected from by the process implementation in the following group formed:

I) adopt roller compactor, wherein regulate described tap density by delivery rate, cylinder gap and mesh size,

Ii) adopt Flat die cuber, wherein regulate described tap density by the gap between described cylinder, mould and die size and cutter speed,

Iii) adopt pin mixing tank nodulizer or rotary drum nodulizer, wherein regulate described tap density respectively by the selection of input speed, moisture content, additive and the rotating speed of concentration and bearing pin or drum;

Iv) fluid process;

V) spray-dryer process; Or

Vi) fluid bed spray dryer process.

29. methods according to any one of claim 23 to 27, wherein said coalescent by being selected from by the process implementation in the following group formed:

I) adopt roller compactor, wherein regulate described tap density by delivery rate, cylinder gap and mesh size,

The cylinder that the expanded graphite particles of wherein said pulverizing is fed to a pair reverse rotation under the help of spiral produces pre-coalescence body, and then fine particle agglomeration step, thus described pre-coalescence body is pushed through the screen cloth helping to limit the agglomerate size of wishing;

Ii) adopt Flat die cuber, wherein regulate described tap density by the gap between described cylinder, mould and die size and cutter speed,

The expanded graphite particles of wherein said pulverizing is pressed through mould by disc type barreling machine cylinder, and then with rotating knife, the graphite granule of described pre-coalescence is cut into the size of described hope;

Iii) adopt pin mixing tank nodulizer or rotary drum nodulizer, wherein regulate described tap density respectively by the selection of input speed, moisture content, additive and the rotating speed of concentration and bearing pin or drum;

Iv) fluid process;

V) spray-dryer process; Or

Vi) fluid bed spray dryer process.

30. methods according to any one of claim 23 to 27, wherein said method comprises grinding expanded graphite meterial further, thus forms the expanded graphite particles pulverized.

31. methods according to any one of claim 23 to 27, wherein said expanded graphite is by following manufacture:

I) graphite material is inserted;

Ii) by described graphite material thermal expansion, thus expanded graphite meterial is formed.

The 32. graphite agglomerate limited any one of claim 1 to 22, by any one of claim 23 to 31 the method that limits obtain.

33. 1 kinds of conducing composite materials, comprise the graphite agglomerate according to any one of claim 1 to 22.

34. 1 kinds of conductive polymerss, comprise:

I) be selected from by the expanded graphite meterial in the following group formed:

A) any one of claim 1 to 22 the expanded graphite agglomerate of pulverizing that limits; And

B) expanded graphite particles of compacting; And

Ii) polymeric matrix.

35. conductive polymerss according to claim 34, wherein said polymeric matrix is formed by following: polyolefine, polymeric amide, polyester, vinylformic acid or acetic ester, polyimide, sulphur/ether polymer, elastomerics, thermosetting resin, their multipolymer or the mixture of any above-mentioned materials.

36. conductive polymerss according to claim 35, wherein said elastomerics is thermoplastic elastomer.

37. conductive polymerss according to claim 34, wherein said conductive polymers has the thermal conductivity substantially the same with substituting polymer composites prepared by agglomerate with the expanded graphite pulverized and mechanical property.

38. 1 kinds for the manufacture of any one of claim 34 to 37 the method for conductive polymers that limits, comprise by any one of claim 1 to 22 the expanded graphite agglomerate of pulverizing that limits be fed in extrusion machine, mix described polymkeric substance and agglomerate thus, and then the conductive polymers obtained is molded as desired form.

39. conductive polymerss according to any one of claim 34 to 37 are for the preparation of the purposes of heat conduction and/or electro-conductive material.